Scale Gem

ok i saw this video on youtube where blendtec blender crushes a handful of Cubic zirconia gems. they rank 8.5 on mohs hardness scale. diamonds rank 10 on the same scale. im arguing with friend about this issue. im saying that diamonds would crush also in the same way as Cubic zirconia gems did. my explanation was that the blender doesnt play that crucial role in the whole process. its the gems that "rub" against each other at high speeds that makes em break up into dust. so what would really happen ? anyone has any idea ?

No, they wouldn't, using Mohs scale, something of the same magnitude will not scratch something else of the same rank on the scale. They would just bounce around for a long time and that is it.